It has become common for individuals and organizations to use networked computers to perform and assist with a wide variety of tasks. Rather than own and maintain physical computer hardware and a suitable data networking environment, it is becoming more and more common to provision virtual computer systems at a specialized provider of such virtual systems. Use of virtual computer systems can provide a number of advantages including cost advantages and/or ability to adapt rapidly to changing computing resource needs. However, conventional virtual computer system provisioning has a number of shortcomings.
Virtual computer systems are ultimately implemented with physical computing hardware and other implementation resources. Nevertheless, a virtual computer system may have an existence, and a configuration, that is independent of the underlying implementation resources. It is not uncommon for particular implementation resources, and even entire implementation resource sets, to be replaced without terminating the virtual computer systems they implement. In this way, virtual computer systems can have relatively long lifetimes. However, as such lifetimes grow longer, various issues can arise with respect to the underlying implementation resources.
The implementation resources used by a particular virtual computer system provider can be changed for a variety of reasons including to enhance technical and/or cost performance. For example, technical advances by a hardware manufacturer may enable more efficient implementation of virtual computer systems. However, implementation resource changes may be incompatible with unchanged virtual computer systems, or virtual computer systems may require reconfiguration to take full advantage of new implementation resources. Insufficiently powerful and/or flexible mechanisms for adapting relatively long-lived virtual computer systems to changed implementation resources can leave the virtual computer systems unusable or operating at an unacceptable level of efficiency.
Same numbers are used throughout the disclosure and figures to reference like components and features, but such repetition of number is for purposes of simplicity of explanation and understanding, and should not be viewed as a limitation on the various embodiments.